Method for processing food wastes

ABSTRACT

A method for continuous processing of raw refuse composed primarily of food wastes and incorporating other wastes such as limited quantities of paper and plastic material wherein the raw refuse material is comminuted and conveyed to a pair of heated platen members and is continuously deposited between the platen members. The heated platens are caused to revolve continuously in such manner as to define a space between the platen members during a portion of each revolution to allow raw refuse material to be conveyed between the platens for depositing, and to cause the heated platens to move into juxtaposition during other portions of each revolution, thereby compressing the comminuted refuse placed therebetween. The platens are caused to revolve at a particular speed that insures compression and complete drying of the refuse during one revolution of the platens. After being compressed and dried by the heated revolving platens the cured refuse is scraped from the platens and is conveyed to a receiving vessel such as a hopper, where the cured refuse may be placed into containers in flake or wafer form or where the cured refuse may be comminuted and then placed into containers.

United States Patent 1191 Lassiter et al.

[ METHOD FOR PROCESSING FOOD WASTES Primary ExaminerPeter Feldman Inventors: Rush E. Lassiter, Hammond; Floyd Attorney, Agent, or F1rm-Arnold, Wh1te & Durkee S. Saizon, Baton Rouge, both of La. [73] Assignee: Floyd Rush Corporation, Baton [57] ABSTRACT Rouge, La. A method for continuous processing of raw refuse [22] Filed: 1974 composed primarily of food wastes and incorporating [21] Appl. No.: 517,491 other wastes such as limited quantities of paper and plastic material wherein the raw refuse material is Related Apphcauon Data comminuted and conveyed to a pair of heated platen Division of N0 348,636, P 1973, members andis continuously deposited between the 3,858,505 platen members.,The heated platens are caused to revolve continuously in such manner as to define a [52] US. Cl. 100/38; 100/95; 241/23; Space betweenthe platen members during a portion of 2 71/14 each revolutionto allow raw refuse material to be [Sl] I111. Cl. B30B 15/34 conveyed between the platens for depositing, and to [58] held of Search loo/93 P, 93 37 39 cause the heated platens to move into juxtaposition lOO/42, 92-98; 241/3, 23, 24, 155, 252, 253; during other portions of each revolution, thereby com- 34/9 20; 71/14 pressing the comminuted refuse placed therebetween. The platens are caused to revolve at a particular speed [561' References that insures compression and complete drying of the ITED STATES PATENTS refuse during one revolution of the platens. After 425,603 4/1890 Fleischman 71/14 being compressedand dn'ed y the heated revolving 603,945 5/1898 Edgerton 100/38 X platens the cured refuse is scraped from the platens 757,706 4/1904 Wilson l00/37 X and is conveyed to a receiving vessel such as a hopper, 2,089,978 8H937 McNaih 71/ 14 X where the cured refuse may be placed into containers 9; 5": 1 in flake or wafer form or where the cured refuse may un 3,611,584 10 1971 Henson 34 12 be commmuted and then placed mm contamers' FOREIGN PATENTS OR APPLICATIONS 8 Claims, 12 Drawing Figures 349,886 l2/l960 Switzerland lOO/1S8 I40 N 02 I I 76 I ,lO 40 I04 98 34 32 96 I00 |3 l22 8 1 l 1l|| Tr- 78 4 3o 36 46 124 CLASSIFICATION 8% E V 0'1 11 I6 84 88 2 I36 "4 1 2o 82 ll I 1 U.S. Patent Oct. 14, 1975 Sheet 2 of5 3,911,808

US. Patent Oct. 14, 1975 Sheet 3 of 5 3,911,808

U.S. Patent Oct. 14, 1975 Sheet 4 0f 5 3,911,808

I447 50 3 I46 PHASE 481 I L I I l l I 1 .|es

L f TOP PLATE BOTTOM PLATE c: 2 30 m 9.5 P.- zo 50 f E I66 0 (I FIG. 7

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US. Patent Oct. 14, 1975 Sheet 5 0155 3,911,808

METHOD FOR PROCESSING FOOD WASTES This is a division of application Ser. No. 348,636 now U.S. Pat. No. 3,858,505 filed Apr. 6, 1973' FIELD OF THE INVENTION This invention is directed generally to the process of curing raw refuse such as food wastes and limited quantities of paper and plastic, etc., by coniminuting, compressing and drying the same and for otherwise preparing raw refuse for use as animal feed, fertilizer, etc. More specifically, the invention is directed to the provision of a method for continuous processing of raw refuse and converting the same into useful products.

BACKGROUND OF THE INVENTION Refuse discarded from dining establishments, from domestic dwellings and from other establishments where food is handled, logically contains a high degree of nutrient value due to the large food content contained therein. Such refuse is typically disposed of by incineration, by composting or by dumping the refuse in pits where it may be covered with a layer of earth to prevent pollution of the atmosphere by odor from the refuse, and to prevent the spread of disease while the garbage is being deteriorated by biological or bacterial action.

Due to the effects of laws restricting ocean dumping of shipboard waste of all kinds, ocean going vessels must be provided with holding tanks and other storage facilities to contain refuse while the ships are in transit. It is desirable to provide means for processing shipboard refuse to reduce the volume thereof for storage purposes and to render it to a sanitary form. The invention, therefore, although directed particularly to processing of food wastes, or wastes from restaurants and the like, is considered equally applicable to treatment of many other types of wastes such as sewage, for example.

It has been known for a long period of time that refuse having a relatively high food content can be used for animal feed and can be used as a commercial fertilizer. The refuse can be processed in such manner that harmful elements such as glass, metal, paper and the like can be removed therefrom, thereby yielding refuse that is primarily composed of food wastes. The food wastes then can be relieved of most of their water content in any suitable manner, thereby yielding products that are composed largely of the nutrient value of the food wastes. The refuse material so processed then may be utilized as food for certain farm animals such as chickens, hogs and cattle and the like and may be fed to the animals along with other conventional animal feeds to reduce the overall cost of animal feeding programs without sacrificing nutrient value. Also, the nutrient value of wastes such as food wastes, sewage wastes and the like, can be returned to the earth in the form of bacteria free commercial fertilizer to replace losses in nutrient value of farm land caused byfarming operations.

THE PRIOR ART Certain machines have been developed in the past for the purpose of processing raw food refuse and converting the same into useful animal food or fertilizer products. The machines so developed typically have the facility for separating harmful elements from the raw refuse and also drying the refuse to prevent further deterioration of the nutrients contained in the refuse. The resulting demoisturized or dehydrated refuse may then be ground or otherwise prepared in a form suitable for feeding to farm animals or for use as a fertilizer.

U.S. Pat. Nos. 1,101,129, 1,493,335 and 2,089,978 disclose various processes and apparatus for treating and handling material such as food refuse. U.S. Pat. No. 1,493,335 discloses a process whereby food refuse is dried by pressing the refuse between a roller and the surface of a heated plate, thereby accomplishing simultaneous heating and disintegration of the refuse material. U.S. Pat. No. 1,101,129 teaches utilization of an oven for the purpose of heating and drying food waste material. U.S. Pat. No. 2,089,978 teaches drying refuse by passing it on a conveyor through a specially designed oven. Segregation and classification of refuse to salvage waste paper and other materials for reprocessing and to salvage organic waste for composting is taught by U.S. Pat. No. 3,524,594. Other U.S. Pat. Nos. such as 3,061,205 Lavalee and 3,477,649 Dalberg et al., teach solid waste reclamation systems including segregation and classification mechanisms.

Where refuse is processed for reclamation of organic waste, it is typically the case for the refuse products to be merely ground and dehydrated, but it is obvious that organic matter processed in this manner will typically require considerable space for storage. If the refuse material is to be used as a fertilizer, it will be undesirable to employ a finely ground or powdered material because of the difficulty of application in fertilizer distributing machines or in airplane distributing systems. It is desirable, therefore, to compress the organic waste simultaneously with the dehydration process to provide a dense resulting product that requires only limited storage space and which may have a solid particulate configuration that facilitates ease of distribution.

Where food refuse is processed to yield animal food and/or fertilizer and subjected to compression heating and drying, it is typical for such processing to be accomplished in short cycle operations where small batches of food product are compressed and dried at any one time. When food wastes-are processed in this manner, the cost of processing is typically quite high and the commercial feasibility of the food waste processing is adversely affected. It is, therefore, a primary object of the present invention to provide a novel method for food product nutrient reclamation which may be accomplished in continuous manner, thereby yielding a low cost product having exceptional com- .mercial feasibility.

It is a further object of the present invention to provide a novel method for processing food product refuse that effectively yields a very dense compressed product requiring very little storage space and having a solid particulate consistency.

Among the several objects of the present invention is noted the contemplation of a novel method for food product nutrient reclamation that is capable of producing animal feed or fertilizer that is not laden with harmful bacteria.

It is also an important object of the present invention to provide a novel method for food product nutrient reclamation which effectively removes virtually all of the moisture from the refuse material and produces a product that is dense and of relative light weight.

A still further object of our invention contemplates the provision of a method for reclamation of nutrient materials from food product refuse, the method being simple and efficient and the machine being of durable and efficient nature as well as being of low cost.

These and other objects of our inventions will become apparent from the consideration of the following specification and accompanying drawings which form a part of this application. In carrying out the objects of our invention, however, it is to be understood its essential features are susceptible of modification and design and arrangement with only a single preferred practical embodiment of the invention being illustrated and specified herein.

SUMMARY OF THE INVENTION Food refuse, after having been subjected to a classification process for removal of harmful materials such as metal, glass, and the like and which waste may or may not contain certain quantities of paper, plastic, etc., may be conveyed to a refuse processing machine having a food refuse grinding mechanism for initially rendering the refuse to a comminuted essentially slurrylike state. A conveying system, such as a pump and conduit are provided to conduct the slurry to the vicinity of a pair of rotatable heated platens and to deposit the same between the platens. A framework may be provided with roller support means for the purpose of supporting the heating platens and may additionally be provided with a motor powered roller drive mechanism engaging the platens and subjecting them to corotative movement. The platens may be movable, relative one to the other during rotation, to provide a space between the platens during a portion of each revolution within which space may extend a slurry conveyor nozzle for the purpose of depositing the refuse slurry between the platens. As the platens rotate, the space will decrease until the platens move into close juxtaposition, thereby causing even spreading of the slurry deposit and applying compression to the refuse material, which compression increases during rotative movement to a predetermined maximum and then gradually decreases during the remaining portion of each revolution of the platens. Each revolution of the platens is of sufficient duration to achieve effective dehydration of the refuse material, and to cause destruction of most of the bacteria during one revolution of the platens.

After the refuse has been properly compressed, heated, and dehydrated, it may be removed from the platens by a scraper which is effective to cause the cured refuse product to be deposited in a container provided therefor. If desired, a combination scraper and conveyor mechanism may be utilized for effective removal of cured refuse material from between the rotating platens. After the refuse material has been removed from the apparatus, it may be further comminuted, if desired, or it may be immediately placed in containers in flake or particulate form for use as desired.

BRIEF DESCRIPTION OF THE DRAWINGS In order that the manner in which the above recited advantages and objects of the invention are attained, as well as others which will become apparent can be understood in detail, more particular description of the invention, briefly summarized above, may be had by reference to the specific embodiments thereof, which are illustrated in the appended drawings, which drawings form a part of this specification. It is to be understood, however, that the appended drawings illustrate only typical embodiments of the invention and, therefore, are not to be considered to be limiting of its scope, for the invention may admit to other equally effective embodiments.

In the Drawings:

FIG. 1 is a plan view of a refuse processing machine constructed in accordance with the present invention, illustrating the upper platen in full line and showing other operative features of the invention in broken line.

FIG. 2 is a side elevational view of the refuse processing machine of FIG. 1, illustrating the various operative parts thereof in detail and showing in block diagram form classification apparatus for preliminary separation of crude refuse.

FIG. 3 is a pictorial representation in plan view of one of the heated platens of the present invention having parts thereof broken away and shown in section and illustrating the electrical heating elements thereof in both full and broken line.

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3.

FIG. 5 is a fragmentary perspective view of the machine of FIGS. 1 and 2 having a part of one of the platens broken away and shown in section and illustrating continuous depositing of uncured refuse material onto the bottom platen and continuous scraping of cured refuse material from the platens.

FIG. 6 is a vertically expanded perspective view of the refuse processing machine of this invention illustrating the various mechanical parts thereof in detail.

FIG. 7 is an electrical schematic view illustrating the electrical system provided for operation of the mechanism of this invention.

FIG. 8 is a fragmentary elevational view of a modified embodiment of the present invention, illustrating provision of a final grinder mechanism for achieving further communitation of cured refuse material as it is removed from the refuse processing machine by a scraper mechanism.

FIG. 9 is a fragmentary plan view of a modified embodiment constructed in accordance with the present invention illustrating a scraper and chain type conveyor mechanism for removing cured refuse material from the refuse processing machine.

FIG. 10 is a fragmentary sectional view taken along line l0l0 of FIG. 9 and illustrating the scraper and chain conveyor mechanism in detail.

FIG. 11 is a fragmentary plan view of the refuse processing apparatus of FIG. 9 illustrating the conveyor drive gearing mechanism thereof in detail.

FIG. 12 is an elevational view taken along line l2l2 of FIG. 9 and illustrating the cured refuse scraper and conveyor mechanism in elevation.

DESCRIPTION OF PREFERRED EMBODIMENTS With reference now to the drawings and first to FIGS. 1, 2 and 6, a machine for curing food waste refuse material consisting largely of food waste material, but which may also include other non harmful waste materials such as paper, plastic materials, etc., may include a framework comprising a plurality of generally vertically oriented posts l2, l4 and 16, which may be interconnected by a plurality of generally horizontally disposed support elements 18, 20 and 22 to define a structural supporting framework for the refuse processing machine. Roller support elements 24, 26 and 28 may be connected in any suitable manner to the upper extremity of the posts 12, 14 and 16, respectively, and may provide a supporting function for a lower rotatable heated platen 30, having generally planar parallel upper and lower surfaces 32 and 34, respectively. The platen may be provided with a centrally located opening 36, within which may be secured a cruciform shaped structural support element 38 having a portion thereof extending above the planar upper surface 32 and adapted to be disposed in guiding and centering relation with an upper heated platen 40 having a centrally located opening 42 within which the structural element 38 is received. The cruciform configuration of the structural element 38 provides a plurality of guide surfaces 44 that engage a cylindrical surface defining the opening 42 and thereby maintain the upper heated platen 40 in registering alignment with the lower platen 30. 1

To the lower surface portion of the cruciform structural element 38 may be secured a depending shaft 46 having an enlarged head 48 at the upper extremity thereof for securing the shaft 46 to the structural element 38. The head 48 may be provided with a plurality of bolt openings 50 enabling the shaft to be connected to the structural element 38 by means of bolts. Obviously, any other suitable means of connection, such as welding or the like, may be employed for connection of the shaft 46 to the structural support element 38 within the scope of the present invention.

The lower extremity of the shaft 46 may extend through a bore 52 defined within a shaft receptacle or collar 54 connected to each of the horizontal support elements 18, 20 and 22, such as by welding or the like. Bearing elements 56 and 58 may be disposed about the shaft 46 and may provide bearing support for the shaft 46.

A plurality of generally circular electrical conductors 60, 62 and 64 may be connected in fixed relation to the shaft 46 in any suitable manner and may be caused to rotate along with the lower heated platen 30 and the shaft 46. Electrical brushes 66, 68 and 70 may be supported relative to the rotary conductor 60, 62 and 64 by a support bracket 72 that may be fixed in any suitable manner to one of the horizontal support elements 18, 20 or 22.

To the upper portion of the cruciform support element 38 may be fixed a pedestal 74 provided for support of a control console 76 provided generally to control the temperature of the heated platens 30 and 40 as well as providing for control of other functions of the refuse curing mechanism of this invention.

It will be desirable to impart rotation to the upper and lower platens at a particular speed to allow the heated platens to properly cure the refuse material during each revolution thereof.

One suitable mechanism for accomplishing controlled rotation of the platens 30 and 40 may conveniently take the form illustrated particularly in FIG. 2, where the support roller element 17 may be considered a drive roller while the remaining support roller 12 and 14 may simply provide an idler support function. The roller structure 16 may be provided with an elongated drive shaft 78 having a chain drive sprocket 80 fixed in non-rotatable relation thereto. A lower chain drive sprocket 82 may be secured in an output shaft 84 of a reduction gear mechanism 86 that may be, in turn, driven by a rotator motor 88 through a protective clutch 90 or other suitable drive connection. As the motor 88 is energized, a drive chain 92, received by the upper and lower sprockets 80 and 82 may induce rotary driving movement to a drive roller 94 of the roller mechanism 16 and the roller 94 through its frictional supporting engagement with the lower surface 34 of the lower platen '30, may induce rotation to the lower platen. The reduction gear mechanism 86 may be a positive drive mechanism inducing single speed rotation to the lower platen 30, or if desired, may be provided with means for varying the speed of the lower platen.

It is also desirable to achieve corotative movement of the upper platen 40, and according to the present invention, one suitable means for accomplishing such rotary movement may conveniently take the form illustrated in FIG. 2 where a roller support 96 is shown to extend from the upper portion of the support post 16 and to support a roller 98 by means of a shaft 100 that is pivotally connected at 102 to the support 96. A roller,

adjustment element 104 may be provided for adjustment of the pivotal relationship of the shaft 100 relative to the support 96, thereby positioning the upper roller 98 relative to the lower roller 94 and thereby positioning the heated platens 30 and 40 relative to one another as well as establishing sufficient frictional engagement between the platens to achieve simultaneous rotation of both platens.

It will typically be desirable although not always necessary to achieve preliminary classification of refuse material being conveyed to the refuse processing machine of this invention and, therefore, as shown in block diagram type schematic form in FIG. 2., classification, if desirable, may be accomplished in any suitable manner capable of separating harmful objects such as metal, glass, plastic, etc. from the food waste material.

If it is desirable that the refuse to be processed be restricted only to food products, the raw refuse maybe fully classified for removal of metal, glass, plastic or paper. Ordinarily, however, glass and metal materials are removed from the raw refuse and are disposed of separately. It is not undesirable that animal feed, and fertilizer be free of paper and some amounts of plastic. For example, animal feed composed of 80% food wastes and 20% paper and plastic particles is considered acceptable because the paper and plastic materials provided roughage.

The food waste, as shown in FIG. 2 then may be conveyed to a preliminary grinding mechanism, illustrated generally at 106, which may incorporate a hopper 1 08 adapted to receive the food refuse material and to feed the food refuse by gravity into a grinder 100 powered by an electrical motor 112. The grinder may be of any suitable type of capable of rendering miscellaneous food products into a comminuted slurry-like consistency. The comminuted slurry-like material may be conveyed from the outlet 114 of the grinder by a centrifugal pump 116 or by any other suitable conveyor mechanism. The pump 1 16 may be provided with a discharge conduit having a relatively rigid portion 1 18 extending from the pump 1 16 and having a relatively flexible portion 120 extending to the vicinity of the heated platens.

It will be desirable to provide means for continuous depositing of the slurry-like food waste material between the heated platens and, therefore, it is necessary that, at some point during each revolution of the platens, a space be provided therebetween to allow introduction of the slurry-like refuse therebetween. One suitable means for providing a space between the platens for introduction of refuse material may conveniently take the form illustrated particularly in FIG. 2, where the upper heated platen 40 is shown to be provided with a tapered or frustoconical lower surface 122 thereby causing the upper platen to be of substantially greater thickness at the inner periphery thereof than at its outer periphery. As the outer peripheral edges of both of the platens are moved in juxtaposition by the cooperating rollers 94 and 98 to place the surfaces 32 and 122 of the platens into juxtaposition for compression of the refuse material along a line of contact, as shown in the upper left portion of FIG. 2, the opposite sides of the platens will be moved apart as shown in the upper right portion of FIG. 2, thereby providing sufficient space for introduction for uncured refuse material. A discharge nozzle 124 may be connected in any suitable manner to the outlet extremity of the flexible conduit 120 and may be provided with an outlet aperture 126 through which the uncured refuse material may be deposited onto the upper surface 32 of the lower platen 30. As the platens corotate clockwise, as illustrated in FIG. 1, the space between the platens decreases continuously during'rotary movement, first to achieve spreading of the refuse material between the platens and then to achieve compression of the refuse material simultaneously with heating for purposes of curing.

For example, as illustrated in FIG. 1 the refuse material is illustrated as being deposited between the platens at zero degrees of rotation. After approximately 90of clockwise rotation, the space between the platens has beome gradually reduced to the point that very little space remains and the refuse material deposited at Zero degrees will have become spread into a relatively thin layer by the opposing surfaces of the platens as the space reduces. The space will continue to be reduced until the refuse material has been conveyed 180, and at this point the platens will have their closest positioning. After being spread by the platens, the refuse material will be subjected to gradually increasing compression until a degree of maximum compression is achieved at substantially 180 of rotation. As the platen surfaces begin to move apart from 180 rotation to -270, the refuse product will continue to be compressed, but compression will be dissipating gradually. At approximately 285 of rotation, the platens will have become spread sufficiently that the refuse material will no longer be under compression. At this time it will be substantially devoid of water content and will be cured into thin wafer-like form.

As rotation continues, part of the cured refuse material will fall way from the upper platen and will lie loosely on the lower platen, but some percentage of the cured refuse will adhere to the upper platen. It is desirable therefore to provide a means for scraping any refuse material that might have adhered to either of the platens during the curing process. One suitable means for cleaning the platens of any adhering cured refuse material may conveniently take the form illustrated in FIGS. 1 and 2, where a support arm 130 is shown to be secured to one of the vertical posts 12, 14 or 16 and may be provided with an upright scraper support 132 to which a tapered scraper element 134 may be secured in any desirable manner. The scraper 134 may be disposed in angulated relation relative to a radius of the rotaty platens, thereby causing refuse material transported by the platents to engage the tapered scraper element and be conveyed outwardly to the periphery of the lower platen 30, where it may descend by gravity into a waiting container, such as shown at 136. The scraper element 134 is shown to be tapered in order to cause upper and lower scraping surfaces thereof to engage the surfaces 122 and 32 respectively of the platens and scrape them clear of cured refuse material that might otherwise adhere thereto.

As indicated above, the upper and lower platen members are heated. The platens must be maintained within a particular temperature range to achieve complete curing of the refuse material as the platens travel one revolution. Although it is within the spirit and scope of the present invention to vary not only the temperature of the platens to achieve full curing, but also to vary the rotary speed of the platens, it is nevertheless more practical to provide a single speed guide mechanism for the platens, and to ensure complete curing of the refuse material by variation of the temperature range of the platens. As shown in FIGS. 3, 4 and 5 an electrical heating element 138 may be positioned in helical manner within at least one and preferably both of the upper and lower platens and may be connected to a source of electrical potential, such as 220 volt AC, through a manually adjusted thermostat 140 that may be incorporated into the control console 76. A temperature dial 142 may be provided on the control console in order to allow visual inspection of the particular operating temperature of the platens.

The electrical circuitry of the present invention may take the form illustrated shematically in FIG. 7, where a three phase circuit is shown comprising conductors 144, 146 and 148 that may be connected to a source of electrical potential such as 220 volt AC and may be controlled through a master switch 150. Conductors 152 and 154 connected to the neutral conductor 146 and an energized conductor 148, respectively, thereby providing 1 10 volt AC circuit for operation of the various motors of the refuse processing machine. A similar 1 10 volt circuit is also provided by conductors 156 and 158 for energization of a thermostat mechanism, illustrated generally at 160, and including a temperature responsive switch 162 actuated by a thermocouple 164 in response to a temperature sensitive transducer 166 disposed to receive heat from one of the platens 30 or 40. The three phase circuit may be controlled by a relay actuated switch 168 for the purpose of controlling heating of the resistance heating elements 138 of the upper and lower platens.

It may be desirable to utilize the cured, i.e., compressed and dehydrated refuse material as it is discharged in compressed flake form from the refuse processing machine. It may, however, be desirable to provide means for comminuting the processed refuse in the event it is desirable to render the refuse to a comminuted material of smaller particulate size. If further comminution is desired, a means for accomplishing the same may conveniently take the form illustrated in FIG. 8, where a hopper 168 is shown to be disposed in position to receive the cured refuse descending from the lower platen 30. A grinding support structure 170 may be fixed to the refuse processing mechanism of this invention in any suitable manner, such as by bolting as shown in FIG. 8, and may support a grinder mechanism 172 that may be driven by an electric motor 174. White the container 136, shown to be disposed below the discharge outlet of the grinder 172, is depicted to be of rigid nature, it is obvious that the processed and comminuted refuse may be deposited in bags of any suitable type for proper handling and storage. A bagging mechanism of conventional nature may be employed in combination with the refuse processing machine of this invention to provide containerized cured refuse product that may be utilized as animal feed, as an additive for livestock feed or for fertilizer, etc.

Although the scraper element 134, illustrated in FIGS. 1 and 2, is capable of continuously cleaning the upper and lower platens of any refuse material that might have adhered thereto and is capable of discharging cured refuse material from the processing appara-' tus of this invention, it may be desirable to provide a means for positively or more efficiently conveying cured refuse material from between the platens. One suitable means for causing forcible ejection of cured refuse material may conveniently take the form illustrated in FIGS. 9-12, illustrating a modified embodiment of the present invention.

As illustrated in FIG. 9, a chain type conveyor mechanism may be employed to forcibly remove cured refuse material that has been scraped or otherwise loosened from the upper and lower platens and may be utilized in combination with a double bladed scraper that effectively achieves scraping of cured refuse material from the platens. As shown in FIG. 12, a support post element 176 may be connected in any suitable manner to the framework of the processing machine and may include a bearing support 178 that rotatably supports a shaft 180 to which may be non-rotatably secured a drive wheel 182 having the periphery thereof disposed in driven contact with the lower platen 30. A gear 184', also fixed relative to the shaft 180, may be disposed in driving relation with a gear 186 rotatably carried by a shaft 188 fixed to an outboard gear support 190. A conveyor chain drive sprocket 192 may be disposed in nonrotatable relation with the gear 186 and may cooperate with a second conveyor sprocket 194 to support a conveyor chain 196 that may be at least partially positioned within the space defined between the upper and lower platens. The sprocket 194 may be joumaled at 196 for rotation at the free extremity of a scraper element 198 that is in turn supported by a bracket 200 extending in supported relation from the shaft 188.

For the purpose of dislodging cured refuse material that might have adhered to either the upper or lower platen the scraper element 198, as shown in FIG. may be composed of flat metal plate bent back upon itself to define a bifurcated or generally C shaped configuration, defining upper and lower scraping edges 202 and 204, respectively, that are disposed in scraping relation with the upper and lower heated platens. The scraper element 98 may be composed of any suitable metal and may have a spring-like nature that causes the scraping edges 202 and 204 to be urged at all times into scraping engagement with the respective heated platens. This feature insures positive scraping of the material from the platens and yet allows the platen surfaces to have relative movement without loss of scraping contact with the scraper structure.

At least some of the links of the conveyor chain 196 may be provided with spring-like projections 206 that may engage loosened cured refuse material and convey it to the outer periphery of the lower heated platen 30 where it may be allowed to descend by gravity into a waiting container 136 or into suitable conventional bagging apparatus.

As the upper and lower platens revolve, the conveyor drive weehl 182, being in engagement with the outer periphery of the lower most platen 30, will energize the conveyor gear mechanism, thereby driving the conveyor chain 196 and its sprockets 192 and 194. As the endless conveyor chain 196 revolves, the spring-like projections 206 will conduct the loosened refuse material outwardly, thereby removing it from between the platens. The mechanical action of the refuse discharge conveyor will effectively prevent sufficient accumulation of cured refuse material adjacent to the conveyor mechanism that might otherwise cause jamming of the refuse material against the scraper.

In view of the foregoing it is apparent that we have provided a novel machine and method for processing refuse material to yield a dense and dehydrated refuse product that may be suitable for use as animal feed and/or fertilizer. A refuse processing machine, constructed in accordance with the present invention, may be continuously operated for long periods of time for continuous production of cured refuse material, thereby eliminating the disadvantages of batch type refuse processing systems and promoting the commercial feasibility of livestock feed and fertilizer production from food waste. The refuse processing machine of our invention is of low cost, is of simple and efficient nature and may be utilized for long periods of time without excessive costs for maintenance and repairs.

It is, therefore, seen that our invention is one well adapted to attain all of the objects and advantages hereinabove set forth, together with other advantages which will become obvious and inherent from a description of the apparatus itself. It will be understood that certain combinations and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of the present invention.

As many possible embodiments may be made of this invention without departing from the spirit or scope thereof, it is to be understood that all matters, hereinabove set forth or shown in the accompanying drawings, are to be interpreted as illustrative and not in a limiting sense.

What is claimed is:

l. A method of continuous processing of refuse, said method comprising:

comminuting raw refuse;

continuous placement of comminuted refuse between rotating platen members of a refuse processing machine;

continuous compressing of said comminuted refuse between said rotating platen members; continuous heat of said comminuted refuse disposed between said platen members; and

continuous removal of dried comminuted refuse from said platen members during rotation of said platen members.

2. The method recited in claim 1, wherein:

continuous placement of comminuted refuse between said rotating platen members is accomplished by forcing said comminuted refuse through conduit means, said conduit means having outlet means located between said platen members and said comminuted refuse being deposited between said platen members upon exiting from said outlet means.

3. The method recited in claim I, wherein:

continuous placement of comminuted refuse between said rotating platen members is accomplished by pumping said comminuted refuse through conduit means said conduit means having outlet means disposed between said platen members, said refuse being deposited by gravity upon the lowermost one of said platen members upon exiting from said outlet means.

4. The method recited in claim 1, wherein:

continuous compressing of garbage between said rotating platen members is accomplished by causing said platen members to be disposed in spaced relation during a portion of the rotational movement of the same and to move into compressing relation with said refuse during another portion of the rotational movement of said platen members.

5. The method recited in claim 1, wherein:

continuous heating of said platen members is accomplished by applying heat to said platen members electrically, said heat being maintained within a preselected temperature range.

6. The method recited in claim 1, wherein:

continuous removal of dried refuse from said platen members is accomplished by locating scraper means between said platen members and is scraping relation to the refuse contacting surfaces of each of said platen members, said refuse contacting surfaces being scraped continuously by said scraper means to remove any refuse material that might be clinging thereto, said scraper means being oriented relative to said platen members so as to remove refuse material from between said platen members at the terminal portion of the rotational cycle of said platen members.

7. The method recited in claim 1, wherein:

continuous compressing of refuse between said rotating platen members is accomplished by providing one platen member having substantially planar refuse engaging surface means formed thereon and by providing the other of said rotating platen members with a generally conical refuse engaging surface means formed thereon and by rotating said platens simultaneously about angularly oriented axes to cause said refuse contacting surfaces to be spaced during a portion of the rotational movement thereof and to move into compressing relation with refuse disposed therebetween during another portion of the rotational movement thereof.

8. The method of claim 1, wherein:

continuous removal of dried refuse from said platen members is accomplished by providing a refuse removal conveyor mechanism having at least a portion thereof disposed between said rotating platen members, said conveyor mechanism having scraping devices thereon that are movable into scraping relation with said platen members, said removal conveyor mechanism being continuously movable and functioning to cause continuous removal of heated, compressed and substantially dried refuse material from said platen members at the terminal portion of the rotational movement thereof. 

1. A method of continuous processing of refuse, said method comprising: comminuting raw refuse; continuous placement of comminuted refuse between rotating platen members of a refuse processing machine; continuous compressing of said comminuted refuse between said rotating platen members; continuous heat of said comminuted refuse disposed between said platen members; and continuous removal of dried comminuted refuse from said platen members during rotation of said platen members.
 2. The method recited in claim 1, wherein: continuous placement of comminuted refuse between said rotating platen members is accomplished by forcing said comminuted refuse through conduit means, said conduit means having outlet means located between said platen members and said comminuted refuse being deposited between said platen members upon exiting from said outlet means.
 3. The method recited in claim 1, wherein: continuous placement of comminuted refuse between said rotating platen members is accomplished by pumping said comminuted refuse through conduit means said conduit means having outlet means disposed between said platen members, said refuse being deposited by gravity upon the lowermost one of said platen members upon exiting from said outlet means.
 4. The method recited in claim 1, wherein: continuous compressing of garbage between said rotating platen members is accomplished by causing said platen members to be disposed in spaced relation during a portion of the rotational movement of the same and to move into compressing relation with said refuse during another portion of the rotational movement of said platen members.
 5. The method recited in claim 1, wherein: continuous heating of said platen members is accomplished by applying heat to said platen members electrically, said heat being maintained within a preselected temperature range.
 6. The method recited in claim 1, wherein: continuous removal of dried refuse from said platen members is accomplished by locating scraper means between said platen members and is scraping relation to the refuse contacting surfaces of each of said platen members, said refuse contacting surfaces being scraped continuously by said scraper means to remove any refuse material that might be clinging thereto, said scraper means being oriented relative to said platen members so as to remove refuse material from between said platen members at the terminal portion of the rotational cycle of said platen members.
 7. The method recited in claim 1, wherein: continuous compressing of refuse between said rotating platen members is accomplished by providing one platen member having substantially planar refuse engaging surface means formed thereon and by providing the other of said rotating platen members with a generally conical refuse engaging surface means formed thereon and by rotating said platens simultaneously about angularly oriented axes to cause said refuse contacting surfaces to be spaced during a portion of the rotational movement thereof and to move into compressing relation with refuse disposed therebetween during another portion of the rotational movement thereof.
 8. The method of claim 1, wherein: continuous removal of dried refuse from said platen members is accomplished by providing a refuse removal conveyor mechanism having at least a portion thereof disposed between said rotating platen members, said conveyor mechanism having scraping devices thereon that are movable into scraping relation with said platen members, said removal conveyor mechanism being continuously movable and functioning to cause continuous removal of heated, compressed and substantially dried refuse material from said platen members at the terminal portion of the rotational movement thereof. 